Which of the following equations is in standard form a) 5x+5y=35 b) 2x-9y=15 c) -y=2x d) y=-2x+3

Tim's phone service charges $23.06 plus an additional $0.22 for each text message sent per month. if tim's phone bill was $28.56, which equation could be used to find how many text messages, x, tim sent last month?

One line passes through (-7,-4) and (5,4) . another line passes through the point (-4,6) and (6,-9)

How do you find the circumfrance of a circle?